raise TypeError, "base_ring (=%s) must be a commutative ring"%base_ring

572

if not base_ring.is_commutative():

573

warn("""You are constructing a free module over a noncommutative ring. Sage does not have a concept of left/right and both sided modules be careful. It's also not guarantied that all multiplications are done from the right side.""")

574

#raise TypeError, "base_ring (=%s) must be a commutative ring"%base_ring

doctest:357: UserWarning: You are constructing a free module over a noncommutative ring. Sage does

2404

not have a concept of left/right and both sided modules be careful. It's also

2405

not guarantied that all multiplications are done from the right side.

2406

doctest:573: UserWarning: You are constructing a free module over a noncommutative ring. Sage does not have a concept of left/right and both sided modules be careful. It's also not guarantied that all multiplications are done from the right side.